John is a Research Fellow at the Scottish Centre for Administrative Data Research (SCADR), University of Edinburgh. His research uses linked administrative data to examine inequalities in health and mortality among people who use drugs, with a focus on the role of criminal justice contact and wider social vulnerability.

He recently completed his PhD at the University of Glasgow, where he examined mortality among people accessing specialist drug treatment in Scotland. Using linked data from the Scottish Drugs Misuse Database and mortality records, his research explored how different types of criminal justice contact relate to health outcomes and risk of death.